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-   -   BA A319 missing winglet (https://www.pprune.org/tech-log/156297-ba-a319-missing-winglet.html)

c152pilot 19th December 2004 16:26

BA A319 missing winglet
 
Hi,

Can somebody tell me why some of BA's A319/A320's are missing one of their winglets (i know that the A320-100 has no winglets)

For example - http://www.!!!!!!!!!!!!!!/open.file/737544/L/

Thanks

c152pilot

Notso Fantastic 19th December 2004 17:13

Short spares/just failed and cleared to operate until hangar time available/whatever. They are of very questionable effectiveness and not at all necessary for the operation. Flying without one or both makes no difference and probably barely burns much more than a few kgs of fuel. So there is no great compulsion to pull an aeroplane out of service for repairs. They're nice to have, they are not important.

c152pilot 19th December 2004 17:16

hi,

thanks for that, always wondered

RoyHudd 19th December 2004 17:54

Yeah right. Winglets are no real use.....So please provide a proof source for that statement. Subjective views are worthless in this arena. And if you have published evidence which is convincing to all of us, my apologies in advance.

Notso Fantastic 19th December 2004 18:04

Well they are so vital the 757/767/777 don't even have them. Winglets are of questionable value to a shorthaul aeroplane where a high percentage of the flight is at lower speeds. They are optimised more for the high speed cruise. Even the 747 with its 6 foot winglets can quite happily fly without one. And the pilots wouldn't even begin to notice!

YOU show where your difference of opinion is valid considering BA is quite happy to send a 319 out on passenger service without one for an extended period!

hawk37 19th December 2004 18:53

Not so sure they're optimized for high speed cruise. Perhaps LRC or max range cruise, where there will be more induced drag that can be minimized by the winglets.
In fact, I'd guess that in some applications, max speed may be REDUCED due to the decreased induced drag at high speeds, and the profile/wetted drag itself of the winglet
Of course, I could be wrong.

Hawk

Notso Fantastic 19th December 2004 19:31

I don't think those miniscule winglets of the Airbus make an appreciable difference.!

Golf Charlie Charlie 19th December 2004 19:57

<<<
I don't think those miniscule winglets of the Airbus make an appreciable difference.!
>>>

So what's the point of fitting them, as one assumes they're not there for decoration ?

I understand the theory of winglets (eg. 744, 738, A330) which tend to confer a fuel benefit over cost for sectors of 3 or more hours, but what of the Airbus-style wingtip fences (which I believe is their proper name) ?

VC10 Rib22 19th December 2004 19:57

Notso,
I believe the very fact that the airbus engineers managed to convince the airbus and B.A. bean-counters on the cost/benefit issue answers the worthiness of winglets. However, I do agree with you that the efficiency of winglets reduces with range, but to counteract this, de-rated take-offs, and hence savings in fuel and engine life cycles, must be the overriding factor.

RE: G-EUPA's situation - I imagine as soon as spares become available, and a suitable slot time in her schedule arises, she will have a pair of winglets fitted. Time will tell.

Regards,

VC10 Rib22

ps although this is a different aircraft, I'm sure the the theory is similar http://www.b737.org.uk/winglets.htm :ok:

Notso Fantastic 19th December 2004 21:42

One doesn't doubt that winglets pay for themselves over time. But not so much that one would schedule early maintenance to repair them! Their saving is very small- I very much doubt they pay for themselves over a period of a year or two, but over the lifetime of the aeroplane, yes most certainly they do provide a return in fuel saving.

The whole point of this thread is:
They are not aerodynamically important or essential
Their saving is small
It is not worth downtime to repair them

cirrus01 19th December 2004 22:00

Removed under CDL .............

Considering that BA is struggling with their spares supply ( EWS ) with just about every part for every aircraft, it is no surprise that winglets are missing.

Is there a BA 737 flying that hasn't had a Outboard aft flap rolling robbery ????


:hmm: :hmm:

NigelOnDraft 19th December 2004 22:02

As Notso says, effect of 1 missing is pretty small... In fact, the biggest "cost" of one missing is the inspection required every t/r to ensure the tape is still in place...

I think we have to add a small fuel penalty, even a small RTOW penalty, and I am sure that over many years, the marginal fuel saving pays for the winglet. However, whenever a catering truck knocks one off, we just carry on with a piece of tape in it's place <G> They are supposed to be replaced "at the earliest maintenance opportunity", but since we have no spares, they tend to fly like that for a few months...

flying scotsman 19th December 2004 22:55

had one knocked off one of my 320s a few years back and was able to MEL it as I recall.

I did look into it a bit deeper and found out that it was reputed to have a 2% fuel detriment for having removed it.

2% over the life of an aircraft is a huge amount of money.

goates 20th December 2004 00:08


Well they are so vital the 757/767/777 don't even have them.
From reading various articles and books about aircraft design, it appears the use of winglets, depends on the engineers. The wing can be designed with the same efficiency without the use of winglets as a different wing has with them. The 777 uses a raked wingtip to give the same effect. For older designs, it may be easier to attach winglets (real ones, not the tiny A320 type) like the new ones showing up on 737s. On new aircraft, it could go either way. Apparently adding winglets can be like adding several more feet to each wing, which reduces drag and increase lift.

Are they essential? It doesn't look like it.

I'm not an airline pilot, or an aeronautical engineer. Just someone who was very interested in this topic before.

DBate 20th December 2004 00:39

@ RoyHudd
 

Yeah right. Winglets are no real use.....So please provide a proof source for that statement.
CDL 8.57-1

b) Complete Wing Tip Fence

One may be missing provided:
1) exposed interior structure is covered, and
2) takeoff and approach climb limiting weight is reduced by 4%, and
3) fuel consumption is increased by 1,4%, and
4) wing tip fence must be replaced at the earliest maintenance opportunity and meanwhile, protective material must be inspected, before every flight and replace if necessary.
5) reduce one engine inoperative ceiling by 300ft.

Maintanance procedure required prior to each flight.


Hope this evidence is convincing enough. ;)

So long,
DBate

mutt 20th December 2004 04:49


Even the 747 with its 6 foot winglets can quite happily fly without one. And the pilots wouldn't even begin to notice
Very true, but with a 9435 Kgs reduction in performance limited takeoff and landing weights, it shouldnt take long for the bean counters to notice that they are losing money!

Strangely enough, I remember that the -400 used to have a fuel flow increase with this CDL, however its no more!

Mutt.

RoyHudd 20th December 2004 06:31

Hmmmm
 
Standard ME/CDL stuff. Allowing an aircraft to be flown with those provisions surely infers that the winglet is of real use, particularly in fuel savings. Maintenance costs, involving close inspections after every flight are not minimal, especially when time is precious down-route.

If we discounted every item covered in the MEL as not necessary for flight, there wouldn't be much left.

But thanks for the proof source DBate, which should help close this discussion. (Maybe!)

FlightDetent 20th December 2004 06:51

So to continue on a different issue, what makes an aircraft lose a winglet (apart from the obvious hangar door)?

Do they tend just to fall off? I've been told that the "elephant ear" on a 737 classic likes to part ways down&south from time to time...


Anyone?
FD

(flap track body fairing if that term had no english speaking ancestor)

BEagle 20th December 2004 07:22

Not sure what sort of an image is presented to fare-paying passengers by an airline whose aircraft have obvious bits missing and bodge tape in their place....? Particularly a 'major carrier'!

Are these winglets intentionally frangible to allow for idiots in catering trucks who drive into aeroplanes?

Poor old Nigel really does seem to be suffering rather with this clever new spares supply system.

NigelOnDraft 20th December 2004 07:56


Are these winglets intentionally frangible to allow for idiots in catering trucks who drive into aeroplanes?
I think they must be... If they were "firmly" attached then the subsequent inspections and potential for serious damage would be huge.


Poor old Nigel really does seem to be suffering rather with this clever new spares supply system.
Whilst I would not disagree with this statement, IMHO it does not apply to Airbii winglets. They were "in short supply" well before EWS. I had queried what "wing tip fence must be replaced at the earliest maintenance opportunity" meant when I had one missing. Problem is all the way back to Airbus - lack of spares - and also something along the lines of they need some custom work (in composites?) before fitting i.e. not all are identical.


2% over the life of an aircraft is a huge amount of money
Bear in mind this crude figure is "worst case", so on a typical sector, effect of no winglet on 1 airframe is probably less than 1%. In short term, not a lot. Long term, over a fleet of aircraft, as has been said, huge.


Not sure what sort of an image is presented to fare-paying passengers by an airline whose aircraft have obvious bits missing and bodge tape in their place....?
Couldn't agree more. however not sure a winglet comes into this. Only the spotters will notice the "absence" of a winglet, and the tape is really outward facing. Flap Track fairings are another matter! I tend to brief the CC to answer queries, but not volunteer information until asked, about such matters...


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